1. Field of the Invention
The present invention relates generally to the use of microphones, transducers, or similar devices to amplify the sound of acoustic musical instruments, and particularly, to the mounting of mini- or lavaliere type microphones inside hollow-body stringed musical instruments. Such microphones convert the acoustical vibrations of the instrument into electrical oscillations which are then transmitted to an amplifying device, and finally to a speaker where such oscillations are reconverted into sounds discernable by the human ear. In particular, the present invention involves a mechanism whereby the microphone is mounted inside the instrument.
2. Description of Prior Art
Numerous systems have been devised for the attachment of microphones, transducers, or the like to acoustic musical instruments for the purpose of sound amplification. Hull U.S. Pat. No. 2,430,717 shows a method for mounting a microphone within a cello or string bass by connecting the microphone to the endpin. Salak U.S. Pat. No. 4,404,885 describes an alternative method for connecting a microphone to a string bass. However, both of these designs do not provide a means for moving the microphone in or around the instrument. This is a significant limitation because every individual musical instrument tends to have unique characteristics regarding the optimum location for positioning a microphone. To not permit flexibility in such positioning often limits the quality of sound capable of being reproduced.
Raymond Vernino, in U.S. Pat. No. 4,495,641, teaches a method of attaching a condenser microphone to an instrument by means of a suction cup. Phillip Petillo, in U.S. Pat. No. 4,168,647, shows a method which allows placement of a transducer on a musical instrument by means of a telescoping tube. Both designs permit a limited degree of flexibility in the user's choice of where to locate the microphone or transducer, but provide only for external mounting. Thus, it is possible that the location for the microphone or transducer chosen by the user of such products may impair playing the instrument by being in the vicinity of the hands or other body parts of the player.
Flexible shafts, or goosenecks, have long been employed as a means for mounting microphones, and when so used, do permit a microphone to be positioned in a variety of locations. Most goosenecks are variations of segmented metallic conduit similar to the designs described by E. T. Greenfield in U.S. Pat. No. 630,501. A recent variation from the 1984 catalog of Shure Bros. Inc. shows use of such a gooseneck to mount a microphone. The outer casing of the conduit is sufficiently rigid to support the weight of the microphone, but sufficiently flexible to permit the user to vary the location of the microphone at his or her discretion. The hollow core of the conduit then permits the passage of wires to carry the signal from the microphone to the amplifier and finally the speakers.
Such goosenecks, when mounted on weighted stands, have proven effective in amplifying acoustic musical instruments. However, the player is forced to remain in the immediate vicinity of the microphone for the duration of the performance. That restriction on movement may limit artistic expression and/or be physically uncomfortable for the player.
Attempts to use such goosenecks for mounting a microphone inside an acoustic musical instrument have met with limited success. However, most previous gooseneck designs do not have sufficient movement to position the microphone in the exact location required to obtain the best possible sound reproduction. Even when an appropriate location can be obtained, prior art goosenecks are not sufficiently rigid to support the weight of the microphone, which thus tends to drift to another location and/or impact structural members of the instrument when it is moved or jostled. Such impacts cause undesirable noises which are then amplified.
A further problem encountered when microphones, transducers, or the like are mounted inside musical instruments is presented in providing a means for connecting the signal wires embedded in the sheathed cable from the microphone to the amplifier. The most common solution employed is to install a long panel output jack, such as Switchcraft model no. 151, in the butt of the instrument. A patch cord with 1/4" phone plugs and/or audio connectors can then be used to connect the output jack to the amplifier. When the outer flange is properly modified as shown in FIG. 10, it can then function both as an output jack and a button for holding the player's strap.
Use of such a jack is limited, however, by the fact that it must be inserted from the exterior of the instrument. This means that the diameter of the mechanism components can be no greater than the hole in the butt of the instrument, normally 7/16" to 1/2". This is a significant limitation, as many models of lavaliere microphones or the mechanisms needed to mount such properly are of a greater diameter. A further disadvantage when using a conventional output jack is that the installer must reach inside the instrument with his or her hand and a wrench to install and tighten the threaded locking nut onto the output jack. For persons with large arms and/or instruments with small soundholes, such access may be impossible.